2016/09/21

06:30

Today is the last day of summer.

06:58

The resource accessor will need a specific means of obtaining a set of
resources under a given name and returning a kind of reference to them. This
would be used so that ServiceLoader operates correctly in launched programs.

10:44

This means the build system refactor has been completed. I just need to test
it on Windows.

12:27

I am considering moving all of my developer notes to outside of the repository
and into unversioned space. However, I would need an efficient means of editing
them. For the most part, any notes that I do write remain the same and sort
of bloat the repository. It would considerably cut down the number of revisions
where I just type notes.

12:39

I would need to rewrite some of the blog scripts however. Although it should
make things a bit easier and remove a project containing notes.

13:42

So now I moved my note system into the unversion space, and I am using nano
right now to write them as needed. I suppose that would be much better when
it comes to the future size of my repository and checkout since the notes
take up quite a considerable amount of space.

13:46

Of course I have to wait a day to see if my script works the same still.

14:03

I am very much contemplating shunning all of the old blog files along
with any commits which only contain note based changes. That would
considerably cut the number of commits performed. To do this, I can
download the manifests for every revision and extract the information
to get the SHA-1 sums of the files to shun, the notes related stuff.
But for a just in case, I suppose only if their size is at least 13
bytes or perhaps even 12. This would be for the header and the hope
would be that the SHA-1 is unique enough with these few bytes so
that nothing else gets accidently shunned. What I can do is use the
timeline command as:
fossil timeline -n 0 -p src/developer-notes/ -t ci -v -W 0. Then
I can read on DELETED, REMOVED

14:14

Although that would be a bit ugly. I can easily shun just the note
files easily however. There is the fossil purge command however.

14:28

Well, shunning can completely break my repository especially since
many of the changes were made long ago. So it would be best if I did
not do such a thing. I could probably recreate the repository and
rehost it, but that would be much work especially when it comes to
tickets and such.

15:56

Not much programming today though, so I suppose that I can work on
the JavaDoc generator potentially or continue on with the JIT.

18:12

I do have to get used to the new note system to prevent cases where I
accidently remove notes and such. However, allocation of registers is
seemingly rather simple.

18:19

Something that could be handy would be indirect dependencies, but that could
get confusing to implement. Basically, if I change a base project it does not
mean that all projects that depend on it have to be rebuilt. That could lead
to strange issues and potentially bugs however.

18:42

One nice thing is that I can write notes out of band of actual code now,
which is nice. I had always tried to keep any notes I have written if they
were completely different in their own commits. One thing I need to actually
work on is the launching system, I noticed a slight sluggish speed when it
comes to launching. This is likely due to the single streamed ZIP opening and
closing constantly, which requires the ZIP table to be parsed over and over
again. However, what I can do is rewrite the ZIP code so that directory
searches are not that costly. That is, the central directory entries are
parsed as they are iterated. I could also potentially perform some caching
of entries or resources.

18:48

One thing to consider in my native code writer factories is that I do not pass
a stream at all, so there is actually no way to write the actual bytes needed
for output. So the factory will need to be given an output stream where there
can be some common instruction building OutputStream variant that is more
friendly to the architecture being written. Then this way there can just be a
base class which architecture specific code wraps accordingly. So in effect,
there would be a MIPSOutputStream for the most part which has special
methods for writing all varieties of instructions.

19:09

One thing to consider is that RISCs will be very similar when it comes to how
they generate code. For example they do not have memory to memory operations
for one. So in hindsight, there will be duplicated in the MIPS and PowerPC
native code writer classes in some areas because they essentially will be
doing the same exact thing.

19:20

Looks like the builder may be using the wrong set of dependencies. For the
MIPS project I am trying to build it fails because it cannot find RISCWriter,
so as such I believe it is potentially using the binary project's dependencies
rather than the sources.

19:25

Also for the ZipFile code, when I refactor it. Due to the fact that I now have
SortedTreeMap, I can lazily populate entry names for lookup. So say that for
example an entry needs to be found. It will iterate through the contents of
the ZIP and then it will fill the map accordingly. If the map already has the
entry then that will be checked first and returned. If all entries have been
read then there will be no linear search at all. So essentially this allows
entries to be retrieved on an as-needed basis. One thing to consider is that
this would increase the package manager speed because usually the manifest
will be written first, so a request of the package information will be a
O(1) operation. Also, if I can know the position of the start of the central
directory then it would also be possible for the base positions to not be
known until linear scan time. This way if a ZIP is opened and only the first
few entries are used, it does not waste time calculating everything else.

19:31

The ABI will need scratch registers for copy operations to be effective. This
will definitely be needed by the RISC code writer for stack to stack
operations.

19:35

So I will definitely need to refactor the ZipFile code. However not working
on the allocator much for some days has somewhat cleared my mind of it.